1. Fields of the Invention
This invention relates to new 5-fluorouracil derivatives useful for an anticancer medicine or intermediates thereof and processes for producing thereof.
2. Description of the Prior Art
Hitherto, 5-fluorouracil and its derivatives such as 1-(2-tetrahydrofuranyl)-5-fluorouracil, 1-hexylcarbamoyl-5-fluorouracil, etc. has been known an anticancer medicines.
However, as these compounds have toxicity, they exert a bad influence upon a living body. In case of doses for oral administration, there are disadvantages of digestive troubles. For this reason, when these compounds are dosed as an anticancer medicine, they need to have lower toxicity. In case of being lower in toxicity, the anticancer effect is lower, so that there is a problem that the anticancer medicine must be dosed in large quantities. Further, it is difficult to refine a desired product and to get a purified compound.